Process of manufacturing new arsenic oxides or arsenobenzols



FATEWW @FWQE.

AUGUST ALBERT, OF MUNICH, GERMANY.

IROCESS OF MANUFACTURING NEW ARSENIC OXIDES OR ARSENOBENZOLS.

No Drawing.

To all 1071/0712, it may concern:

Be it known that I, AUGUST'ALBERT, a citizen of the Republic of Germany, and residing at Munich, Elisabethstrasse 46, Ger many, have invented a new and useful Process of Manufacturing New Arsenic Oxides or Arsenobenzols, of which thefollowing is a specification.

In a patent application entitled Process of manufacturing derivatives of organic arsenic compounds, filed simultaneously herewith, Serial Number 546,792, I have described a method of producing hydrazine compounds with arsenic by reacting a hydrazine compound with a. mixed aromatic, aliphatic carbonyl arsenic compound. I have now discovered that the resulting products can be reduced by sodium hydrosulphite. phosphorus trichloride, phosphorous acid, mixed hydrogen iodide and sulphurous acid. sodium bi-sulphite, and the like in such a manner that the arsenic acid nucleus only is attacked, and the complicated hydrazone structure with its double linkings remains unchanged.

This selective reduction of the arsenic group may be stopped when the pentavalent arsenic has been reduced to oxide as the initial trivalent stage, thus RAS0 H+HQ=RAS=O +211 on or the reduction may be continued until the arsenobenzol isproduced in which the ar- I will now give several examples which will serve'as illustrations of these methods of practising my invention. However my invention is not limited to the examples cited, as it is capable of being practised by other methods.

1. 2.9 g. semicarba-zone of the p-benzaldehyde arsenic acid:

ASOgEIz are dissolved in one mol of sodium hydrate and the solution made up wlth water to about Specification of Letters Patent.

Patented Aug. 15, 1922.

Application filed March 25, 1922. Serial No. 546,793.

cc. This solution is added with continued stirring to a solution of 4 g. chloride of magnesium and aoout 29 g. sodium hydrosulphite in 50 cc. water. It is then heated with stirring to 50 or for two hours. Arsenobenzol of an intense yellow color separates out. .This must be sucked on, preferably under vacuum, washed with water and dried in vacuum.

2. 45 cc. of dried acetic ester is oured over 3 g. of semicarbazone of p-acetop enonarsonic acid;

ASOsHz 6 cc. of phosphorus trichloride are then added with water, cooled and stirred. The semicarbazone dissolves to a clear solution by this treatment. The reaction mixture is then allowed to stand for several hours in a closed vessel and then finally the acetic ester and phosphorus trichloride are evaporated on a water bath as far as possible. The oily residue becomes solid when treated with a solution of sodium carbonate as the desired arsenic oxide separates out.

3. 1.3 g. of the malonylhydrazone of pacetophenonarsonic acid;

are brought in solution with 20 cc. of NaOH solution and 80 cc. water. To this solution 13 g. sodiumhydrosulphite are added; the solution, heated to about 60 is then well stirred for 1 or 2 hours. The separated yellow arsenobenzol is sucked off, washed well With water and dried in vacuum. When heated in a capillary tube to about 330, it beginsto darken without melting.

4. Over 1. g. of the Y semicarbazone of p-acetophenonarsonic acid, is poured with 5 cc. of a solution of sodium bisulphite and boiled up several times under a reflux cooler. The reduction is thereby for the most part completed. The solution is then preferably allowed to stand on the v its): hath for e hoiff an hour or an nous; the corresponding arsenic oxide is then sucked off Well Washed With Vitli'fil. The 0 n E has the some properties as those noted under example 2.

It may he redissolved in Nevi solution and reprecipitated by a solution of ammoniumchloride as a snow whlte iroduct. When heated in a-cepillery tube it shows no change and no melting below 360.

5. 0.6 g. semlcerbezonc oi 11on-1-oXy-S arsenic OXidG;

are stirred with 6 cc. methyl uicohol end to the ecetophe- 7 this suspension is added 2.5 cc. of on 8 times of the phenyihydi'uzone of i-oxyabout" lutiou allowed to stand in Well closed vessei for nouns and. then the corresponding ei-senic oxide is filtered off with suction. may be redissolved in NeUH solution and isi'epi'ecipiteted es a light yellow brown powdei' by a solution of ammonium chloride. When heated in e capillary tube, it decomposes explosively at about 270 and darkens in coioi'.

Claims: y

1. Process of preparing a compound containing trivalent arsenic and e hydrezone group which consists in treating "Wih a reducing-agent an aromatic compound Which contains an arsenic acid group attached to the henzol nucleus and a hydrazine group attached to the benzol nucleus through ourbon.

2. Process of preparing a compound containing trivalent arsenic and u hydrazone' group Which consists in treating with sodium hydrosulphite an aromatic comound Which contains an sirsonic acid group attached to the benzol nucleus and a hydrazine attached to the benzol nucleus through carbon.

3.- As a new compound, an ersenohydiezone oi thetype :ASRz-c in which he represents ilent iii-sonic, R represents hydrogen on an elkyl gsoup R "represents a phenyl group and represents 21 group containing a hydrazine nucleus.

As a new compound, the semi-curbezone of p-urseno heniuldehyde. 

